Eleonora Benatti

Choroidal Findings in Dome-Shaped Macula in Highly Myopic Eyes: A Longitudinal Study

PURPOSE To describe choroidal findings in dome-shaped macula associated with high myopia using fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral-domain optical coherence tomography (SD OCT), and to elucidate the mechanism and natural course of serous retinal detachment (RD) associated with dome-shaped macula. DESIGN Retrospective, observational case series. METHODS We reviewed longitudinal imaging results of 52 highly myopic eyes with dome-shaped macula. Changes on FA and ICGA were assessed. Retinal, choroidal, and scleral thicknesses and bulge height were measured on SD OCT. RESULTS Serous RD was the most common abnormality associated with dome-shaped macula, detected by SD OCT in 44% of the cases with no associated choroidal neovascularization. Significant differences in the proportion of eyes with pinpoint leakage on FA (P < .001), punctate hypercyanescence on ICGA (P < .001), and pigment epithelium detachment on SD OCT (P < .001) were noted inside the inward bulge of the staphyloma between eyes with and without serous RD. Serous RD was not associated with hyperpermeability areas on ICGA. Eyes with serous RD had thicker choroid (P = .004) and tended to have thicker sclera (P = .067) and greater bulge height (P = .079). Choroidal thickness, scleral thickness, and bulge height were positively correlated (P < .01). All eyes presented a fluctuating course of serous RD during follow-up. Worsening of serous RD was associated with appearance of new punctate hypercyanescent spots on ICGA and leaking points on FA (P < .001 and P = .016, respectively). CONCLUSION Serous RD in dome-shaped macula was likely caused by choroidal vascular changes, similar to central serous chorioretinopathy, but specifically confined in the inward bulge of the staphyloma and secondary to excessive scleral thickening. Serous retinal detachment showed fluctuating changes over time, with alternating active and inactive stages. Angiographic findings in dome-shaped macula suggest the choroid as a target for possible treatment strategies.

Accuracy of the Heidelberg Spectralis in the alignment between near-infrared image and tomographic scan in a model eye: a multicenter study

PURPOSE To evaluate temporal changes and predictors of accuracy in the alignment between simultaneous near-infrared image and optical coherence tomography (OCT) scan on the Heidelberg Spectralis using a model eye. DESIGN Laboratory investigation. METHODS After calibrating the device, 6 sites performed weekly testing of the alignment for 12 weeks using a model eye. The maximum error was compared with multiple variables to evaluate predictors of inaccurate alignment. Variables included the number of weekly scanned patients, total number of OCT scans and B-scans performed, room temperature and its variation, and working time of the scanning laser. A 4-week extension study was subsequently performed to analyze short-term changes in the alignment. RESULTS The average maximum error in the alignment was 15 ± 6 μm; the greatest error was 35 μm. The error increased significantly at week 1 (P = .01), specifically after the second imaging study (P < .05); reached a maximum after the eighth patient (P < .001); and then varied randomly over time. Predictors for inaccurate alignment were temperature variation and scans per patient (P < .001). For each 1 unit of increase in temperature variation, the estimated increase in maximum error was 1.26 μm. For the average number of scans per patient, each increase of 1 unit increased the error by 0.34 μm. CONCLUSION Overall, the accuracy of the Heidelberg Spectralis was excellent. The greatest error happened in the first week after calibration, and specifically after the second imaging study. To improve the accuracy, room temperature should be kept stable and unnecessary scans should be avoided. The alignment of the device does not need to be checked on a regular basis in the clinical setting, but it should be checked after every other patient for more precise research purposes.

Evaluation of retinal nerve fiber layer thickness measurements for glaucoma detection: GDx ECC versus spectral-domain OCT

Background:To assess the ability of retinal nerve fiber layer (RNFL) thickness measurements obtained using GDx-enhanced corneal compensation (ECC) or spectral-domain optical coherence tomography (RTVue), and that of ganglion cell complex (GCC) scan available on RTVue, to detect glaucoma. Methods:One randomly selected eye of 205 subjects (70 normal, 65 ocular hypertension, and 70 glaucoma) underwent a complete clinical and instrumental examination. RTVue spectral-domain optical coherence tomography was used to assess RNFL thickness and GCC parameters, GDx ECC to assess RNFL thickness. Areas under the receiver operating characteristic curves (AUCs) and sensitivity of the RNFL and GCC parameters were calculated at a fixed specificity of 95%, and the diagnostic abilities of the RNFL values obtained using the 2 instruments were compared. We also compared the results obtained in the normal, ocular hypertensive, and glaucomatous subjects. Results:Best GDx RNFL parameter was nerve fiber indicator (NFI) (AUC 0.99, sensitivity 96%); the best RTVue parameters were average (AUC 0.98, sensitivity 90%), inferior-temporal (AUC 0.97, sensitivity 89%), and superior-temporal RNFL thickness (AUC 0.96, sensitivity 87%). There were no significant differences between the 2 devices (P>0.05). Best GCC parameters were focal loss volume (AUC 0.98, sensitivity 91%) and global loss volume (AUC 0.96, sensitivity 87%). Conclusions:GDx ECC and RTVue show a very good diagnostic ability to detect glaucoma. Most of the RNFL parameters had high AUCs and sensitivities. The diagnostic validity of GCC was comparable with that of the RNFL parameters, and they may be very useful in detecting RNFL damage.

The loss of macular ganglion cells begins from the early stages of disease and correlates with brain atrophy in multiple sclerosis patients

Background: The importance of neurodegeneration in multiple sclerosis (MS) is increasingly well recognized. Objectives: To evaluate retinal pathology using optical coherence tomography (OCT) and to investigate possible associations between retinal layers’ thickness and specific patterns of gray matter volume in patients with a new diagnosis of MS. Methods: A total of 31 patients underwent OCT scans and brain magnetic resonance imaging. In total, 30 controls underwent the same OCT procedure. The association between focal cortical volume and OCT measurements was investigated with voxel-based morphometry (VBM). Results: Compared to controls, patients’ macular retinal nerve fiber layer (mRNFL), macular ganglion cell layer (mGCL), macular inner plexiform layer (mIPL), and macular ganglion cell-inner plexiform layer (mGCIPL) thickness were significantly reduced (p = 0.0009, p = 0.0003, p = 0.0049, and p = 0.0007, respectively). Peripapillary RNFL (pRNFL) and temporal sector pRNFL (T-pRNFL) did not show any significant changes, although there was a trend toward T-pRNFL thinning (p = 0.0254). VBM analysis showed that mGCIPL and pRNFL were significantly correlated with the volume reduction of occipital-parietal cortex (p < 0.005). Conclusion: mRNFL, mGCL, and mIPL are significantly reduced in MS patients without concomitant pRNFL thinning. These retinal changes show a significant association with cortical regions that are known to be important for visuospatial performance.

Sickle cell maculopathy: Identification of systemic risk factors, and microstructural analysis of individual retinal layers of the macula

Purpose To identify systemic risk factors for sickle cell maculopathy, and to analyze the microstructure of the macula of Sickle Cell Disease (SCD) patients by using automated segmentation of individual retinal layers. Methods Thirty consecutive patients with SCD and 30 matched controls underwent spectral-domain optical coherence tomography (SD-OCT) and automated thickness measurement for each retinal layer; thicknesses for SCD patients were then compared to normal controls. Demographic data, systemic data, and lab results were collected for each SCD patient; multivariate logistic regression analysis was used to identify potential risk factors for sickle cell maculopathy. Results Ongoing chelation treatment (p = 0.0187) was the most predictive factor for the presence of sickle cell maculopathy; the odds were 94.2% lower when chelation was present. HbF level tended to influence sickle cell maculopathy (p = 0.0775); the odds decreased by 12.9% when HbF increased by 1%. Sickle cell maculopathy was detected in 43% of SCD patients as patchy areas of retinal thinning on SD-OCT thickness map, mostly located temporally to the macula, especially in eyes with more advanced forms of sickle cell retinopathy (p = 0.003). In comparison to controls, SCD patients had a subtle thinning of the overall macula and temporal retina compared to controls (most p<0.0001), involving inner and outer retinal layers. Thickening of the retinal pigment epithelium was also detected in SCD eyes (p<0.0001). Conclusions Chronic chelation therapy and, potentially, high levels of HbF are possible protective factors for the presence of sickle cell maculopathy, especially for patients with more advanced forms of sickle cell retinopathy. A subtle thinning of the overall macula occurs in SCD patients and involves multiple retinal layers, suggesting that ischemic vasculopathy may happen in both superficial and deep capillary plexi. Thinning of the outer retinal layers suggests that an ischemic insult of the choriocapillaris may also occur in SCD patients.

Choroidal Structural Changes Correlate With Neovascular Activity in Neovascular Age Related Macular Degeneration

Purpose To correlate changes in choroidal thickness and vascularity index with disease activity in patients with neovascular age-related macular degeneration (nAMD). Methods Eyes diagnosed with AMD that had two sequential visits within 12 months and that had no choroidal neovascularization (CNV) or had inactive CNV at the first visit were included. Those that had active CNV at follow-up were enrolled as cases. Eyes that did not developed a CNV or that were still inactive at the second visit were enrolled as controls. Disease activity was based on optical coherence tomography (OCT) and fluorescein angiography findings. Subfoveal choroidal thickness (SCT), mean choroidal thickness (MCT), and choroidal vascularity index (CVI) were assessed on enhanced depth imaging OCT and compared between the baseline and follow-up visit. Subgroup analysis accounting for lesion type and previous treatment, if any, were performed. Results Sixty-five eyes from 60 patients (35 females) and 50 age- and sex-matched controls were included. At the active visit, cases had an increase from 164 ± 67 μm to 175 ± 70 μm in mean ± SD SCT and from 144 ± 45 μm to 152 ± 45 μm in MCT (both P < 0.0001). The mean CVI also increased at from 54.5% ± 3.3% to 55.4% ± 3.8% (P = 0.04). Controls did not show significant changes in choroidal measurements between the two visits. Mean SCT, MCT, and CVI values were similar for previously treated and treatment-naive eyes. Conclusions Choroidal thickness and CVI significantly increased with active disease in nAMD eyes. Changes in choroidal thickness may predict CNV development or recurrence before they are otherwise evident clinically.